import java.util.Scanner;

public class caidan {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入需要进行的操作:");
        String caozuo = scanner.next();
        Scanner scanner1 = new Scanner(System.in);
        System.out.println("请输入第一个数:");
        int a = scanner1.nextInt();
        System.out.println("请输入第二个数:");
        int b = scanner1.nextInt();
        switch (caozuo){
            case"求和":
                int c = a+b;
                System.out.println(c);
                break;
            case"求差":
                int d = a-b;
                System.out.println(d);
                break;
            case"求积":
                int e = a*b;
                System.out.println(e);
                break;
            case"求商":
                int f = a/b;
                System.out.println(f);
                break;
            case"求余":
                int g = a%b;
                System.out.println(g);
                break;
            case"退出":
                System.out.println("退出");
                break;
        }
    }
}